I would say, that it was the best possibility to have ALL options by
clicking F1 Key and have the possibility to define F2 and F3. So you have
some more needed functions on F2 and F3 instead of Invert on/off or scroll
bar on/off...

What do you think about that?

Some other thing I just found out: With Rockbox it seems that the batteries
are needed faster than before? Is this possible? May it be, because i'm
listening with playlists now or does the fast forward need a lot of battery?